public class Student {

    private String name;
    private String mobile;
    private String num;
    private byte gender;//0:male,1:female
    private int age;
    public Student(String name) {
        this.name = name;
    }
    public Student(int age2){
        age=age2;
    }

    public Student(byte gender) {
        this.gender = gender;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Student(String name, String mobile, int age) {
        this.name = name;
        this.mobile = mobile;
        this.age = age;
    }

    void introducemyself(){
        System.out.println("My name is "+ name +".");
        System.out.println("I am "+age+" years old.");
        System.out.println("My phone number is "+mobile+".");
    }
    void Mymobile(){
        if(mobile.length()!=11)
        {
            mobile = null;
        }
    }

    void like(){
        System.out.println("I like reading book.");
    }
    void eat(){
        System.out.println("I like eating.");
    }
}
